Bill de Blasio, left, the top vote-getter in the Democratic primary for New York City mayor, with his son, Dante. / Kathy Willens, AP

by Catalina Camia, USA TODAY

by Catalina Camia, USA TODAY

The 16-year-old Brooklyn Tech student is being credited with giving his father, Bill de Blasio, a big boost in New York City mayor's race. The elder de Blasio was the top vote-getter in Tuesday's Democratic primary and is slightly above the 40% support he needs to avoid a runoff with William Thompson. The winner will face Republican Joe Lhota on Nov. 5.

Dante, with his big smile and even bigger hair, starred in a campaign commercial that helped push de Blasio and the candidate's message of ending economic inequality for New Yorkers to the top of the Democratic field.

"Bill de Blasio will be a mayor for every New Yorker and I'd say that even if he weren't my dad," Dante proudly says in the TV ad.

Nearly 6 in 10 registered Democrats, or 59%, who saw the ad said they liked Bill de Blasio even more after seeing it, a poll by NBC News 4/Wall Street Journal/Marist Institute for Public Opinion showed.

Dante, his hairdo and his dad's strength at the ballot box have combined into one social media phenomenon: the Twitter hashtag #fromentum.

Chiara de Blasio, the candidate's 18-year-old daughter, joked about her little brother's emerging fame while managing to put him in his place. "My brother ... may look good on TV, but there's only one de Blasio who got to vote for her dad today," she said at the candidate's primary night party.

But it was Papa de Blasio who had the best line, celebrating not only his daughter but his son as well.

"In her enthusiasm Chiara just attempted to touch the hair," de Blasio joked. "Security was ready to intervene."